Modern imaging methods in medical technology mean that a doctor, while undertaking a diagnosis for example, is confronted by a plurality of sectional images that he must evaluate. Looking through large numbers of such sectional images is very tiring and as such is liable to errors. On the other hand very great care has to be taken during this task, since the result generally has a decisive effect on the further treatment of the patient.
The desire is accordingly to improve the display of sectional image data. In particular an orientation in a three-dimensional space and in relation to the human body is to be made easier.
In the prior art the practice of displaying additional further orientation images in addition to the image to be displayed or the sectional image on which the examiner is currently concentrating is known. Thus a method from the prior art typically aims to present three correlated views, each orthogonal to each other, which mutually serve as an overview. The orientation images also serve to make the environment of the respective image and relevant anatomic structures rapidly detectable.
Image browsers are also known in the prior art which make it possible to switch back and forth or to scroll between individual images. To obtain an overview of the anatomic structure of the image to be displayed, it is thus known that a switch can be made from the (current) image to be displayed to further images. The further images to which the user can switch are selected from a volume dataset in accordance with a rigid pre-configurable scheme. For example each adjacent fifth, tenth or fifteenth image can be retrieved for further display in relation to the (current) image, so that the user can then switch from the current image to the adjacent images. The disadvantage associated with this is that the doctor, for the purposes of better orientation, must perform a manual user interaction (which once again diverts him from his work), so that he cannot automatically obtain any combined display of the image and the further images.
Although the prior-art browsers mentioned above do offer the user a degree of assistance in orientation—they are also still associated with further disadvantages. On the one hand orientation in the overall volume dataset is only possible with difficulty, since this typically consists of hundreds of individual sectional images. In other words a very large number of sectional images must be viewed. Another disadvantage is that there is no variable adjustment available to the user, but rather the further images that are to be displayed for the current image are defined in the same way in each case. If the volume dataset for a CT examination relates for example to the entire stomach area of a patient and if only the area of the porta hepatis is of interest clinically, with the previous browsers the doctor had to view a plurality of sectional images and so-to-speak “work towards” the image with the porta hepatis. In doing so he must orient himself in the large volume of sectional images in order to arrive at the relevant area. It is easy to see that this method—especially with complex circumstances—is very liable to errors and is inefficient.